Carrier acquisition in a DC/MA system
This invention relates generally to methods and apparatus for acquiring the carrier frequency in a wireless communication system and specifically to a method and apparatus for examining the band edges of spectrally symmetric communications channels to iteratively derive the carrier frequency. Carrie...
Gespeichert in:
Hauptverfasser: | , |
---|---|
Format: | Patent |
Sprache: | eng |
Online-Zugang: | Volltext bestellen |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | This invention relates generally to methods and apparatus for acquiring the carrier frequency in a wireless communication system and specifically to a method and apparatus for examining the band edges of spectrally symmetric communications channels to iteratively derive the carrier frequency.
Carrier wave frequency is quickly acquired without burdensome MIPs requirements by limiting the spectral analysis of the incoming channel to the expected band edges. The right and left band edges spectral energy is compared and clock frequency correction is made from the results of this comparison. A band pass filter, such as a Goertzel algorithm filter, is employed to quickly and with processing efficiency perform the spectral analysis at the band edges. Once the direction of the frequency error is derived, the correct frequency can be acquired through a feedback loop employing various iterative correction techniques, such as a gearshift approach in which certain predefined frequency corrections are imposed in decreasing steps until the desired carrier frequency has been acquired. |
---|